[vpnc-devel] VPNC Front End

[David Rothenberger]

On 2/20/2009 11:15 PM, Joshua Bahnsen wrote:
> I created an open source VPNC Front End for Windows, it is currently 
> hosted on Sourceforge. I'm sending an email to this list because I want 
> to make sure I'm not stepping on any toes. I have not modified any of 
> the vpnc sources, they are just compiled with cygwin. I am providing in 
> an installer the required cygwin libraries:
> 
> cyggcrypt-11.dll
> cyggpg-error-0.dll
> cygiconv-2.dll
> cygintl-8.dll
> cygwin1.dll
> 
> I modified the source of cygwin so I do not interfere with other cygwin 
> applications. It will load in an entirely separate memory space and it 
> uses an alternate registry location.
> 
> I also provide the TAP drivers provided by OpenVPN.
> 
> I'm in the process of setting up the Sourceforge site below, but the 
> main sources and the installer are there.

I applaud this effort, but you need to distribute the source code 
(whether modified or not) for the Cygwin DLLs, and possibly other 
packages like OpenVPN and VPNC itself. Cygwin is GPL'd, so if you 
distribute the binaries, you have to distribute the source, too [1].

I don't see any real reason to use a modified Cygwin DLL. The Cygwin 
folks take great pains to ensure backwards compatibility, so you could 
instruct users to install Cygwin from www.cygwin.com and add the Cygwin 
bin directory to their path [2]. That would obviate the requirement for 
distributing sources.

[1] http://www.gnu.org/licenses/gpl-faq.html#UnchangedJustBinary

[2] Note: Do NOT instruct users to copy the cygwin1.dll to the VPNC 
Front End directory.

-- 
David Rothenberger  ----  daveroth at acm.org

buzzword, n:
         The fly in the ointment of computer literacy.